I have a brand *new* DPMS Lo-Pro 20" Bull Barrel. The barrel is stainless steel. This upper includes a free float tube. I got this directly from DPMS and decided I'm not going to use it. This Upper is complete with the bolt, chrome carrier and charging handle. barrel is marked 223 1/9 twist.

Here is the link to DPMS http://www.dpmsinc.com/10Expand.asp?ProductCode=FTBL-LP